#include <bits/stdc++.h>
using namespace std;

int main() {
	int q;
	scanf("%d", &q);
	priority_queue<int, vector<int>, greater<int>> pq_insert, pq_erase;
	while (q--) {
		int t, x;
		scanf("%d %d", &t, &x);
		if (t == 1) pq_insert.push(x);
		else pq_erase.push(x);
		while (!pq_erase.empty() && pq_insert.top() == pq_erase.top()) {
			pq_insert.pop();
			pq_erase.pop();
		}
		printf("%d\n", pq_insert.empty() ? -1 : pq_insert.top());
	}
	return 0;
}